A large current flowing when energization by normal load drive control is performed at the time of a load short-circuit is prevented. A load drive device 100 includes drive switches 61 and 62 that turn on or off the current supplied from a power source to a load 70, a switch drive circuit 20 that transmits a drive signal to the drive switches 61 and 62 based on a control command from an arithmetic device 10, and a constant current source 40 that supplies the current to the load 70 without passing through the drive switches 61 and 62. Then, the switch drive circuit 20 performs control so as not to turn on either the drive switches 61 or 62 when the voltage between both ends of the load 70 becomes equal to or less than the determination value in a state where the drive switches 61 and 62 are turned off and in a state where the current is supplied from the constant current source 40 to the load 70.

A gate drive device drives a gate of each of two semiconductor switching elements constituting upper and lower arms of a half bridge circuit. The gate drive device detects a peak value of an element voltage that is a voltage of a main terminal of one of the two semiconductor switching elements, as one semiconductor switching element, or a change rate of the element voltage during a change period in which the element voltage changes. The gate drive device determines whether an energization to the one semiconductor switching element during the change period is a forward energization in which a current flows in a forward direction or a reverse energization in which the current flows in a reverse direction.

A driver circuit is configured to deliver drive signals from an output pin to a power switch to control ON/OFF switching of the power switch. A first detection pin of the driver circuit is configured to receive a first signal associated with the power switch, wherein the first signal indicates a voltage drop over the power switch and a voltage drop over one or more other circuit elements. A second detection pin is configured to receive a second signal, wherein the second signal indicates a voltage drop over one or more matched circuit elements, wherein the one or more matched circuit elements associated with the second signal are substantially identical to the one or more other circuit elements associated with the first signal. The driver circuit is configured to determine the voltage drop over the power switch based on a difference between the first signal and the second signal.

An electronic device includes a semiconductor substrate and a bidirectional transistor switch formed on the substrate, the bidirectional switch including a first source node, a second source node and a common drain node. A first transistor is formed on the substrate and includes a first source terminal, a first drain terminal and a first gate terminal, wherein the first source terminal is connected to the substrate, the first drain terminal is connected to the first source node and the first gate terminal is connected to the second source node. A second transistor is formed on the substrate and includes a second source terminal, a second drain terminal and a second gate terminal, wherein the second source terminal is connected to the substrate, the second drain terminal is connected to the second source node and the second gate terminal is connected to the first source node.

The present invention relates to a circuit for protecting a switch of an electrical system, said protecting circuit comprising a variable electronic component having a physical characteristic the value of which varies by at least 10% as a function of temperature, the protecting circuit being configured to prohibit a current from passing through said switch when the intensity of said current exceeds a maximum allowed intensity threshold, said variable electronic component being connected in the protecting circuit such that the value of the maximum allowed intensity threshold is directly a function of said physical characteristic.

In an embodiment, a voltage comparator includes: a first switch having a conduction terminal coupled to an internal node that is coupled to an output of the voltage comparator; a current source; a capacitor; and a second switch connected in parallel with the capacitor, wherein the current source, the capacitor, and the first switch are coupled in series.

An integrated circuit may include a power transistor coupled between a supply pin and an output pin; a current sensing circuit configured to sense a load current passing through the power transistor and to provide a respective current sense signal; a first configuration pin; a current output circuit configured to provide a diagnosis current at a current output pin; a diagnosis pin for receiving a diagnosis request signal; and a control circuit configured to: select a characteristic curve representing a current versus time characteristic dependent on a external circuit connected to the first configuration pin; generate a drive signal for the power transistor dependent on the selected characteristic curve and the current sense signal; and control—dependent on a pulse pattern of the diagnosis request signal—the current output circuit to set the value of the diagnosis current such that it represents the load current or the selected characteristic curve.

A gate drive device drives a gate of a semiconductor switching element constituting an upper or lower arm of a half bridge circuit which supplies an output current, which is alternating current, to a load. The gate drive device detects a peak value of an element voltage which is a voltage of a main terminal of the semiconductor switching element or a change rate of the element voltage when the semiconductor switching element is switching. The gate drive device acquires a maximum value among a plurality of peak values or a plurality of change rates during a predetermined detection period including a period in which the semiconductor switching element performs switching multiple number of times.

A semiconductor device includes a first transistor that flows a current to a load, a current generation circuit that outputs a current corresponding to a power consumption of the first transistor, a temperature sensor, a resistor-capacitor network coupled between the current generation circuit and the temperature sensor and an overheat detection circuit coupled to a connection point of the current generation circuit and the resistor-capacitor network, wherein the resistor-capacitor network comprises a resistor and a capacitor corresponding to a thermal resistance and a thermal capacitance between the first transistor and the temperature sensor.

A solid-state multi-channel protection circuit includes a microcontroller, a current sensor, a plurality of temperature sensors, and first and second multiplexers selectively connecting the current sensor to one of a plurality of solid-state devices and each of the plurality of temperature sensors to the microcontroller. The microcontroller selectively controls the second multiplexer to receive a temperature output associated with one of the plurality of solid-state devices, and selectively controls the first multiplexer to receiver a current output related to the measured current associated with the same solid-state device, wherein the microcontroller provide over-current protection and over-temperature protection based on the received temperature output and the received current output.